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Articles 601 - 630 of 1925
Full-Text Articles in Sedimentology
North-Central Nebraska Geology: Niobrara River Valley In Brown, Cherry, And Keya Paha Counties, R. M. Joeckel, L. M. Howard, S T. Tucker
North-Central Nebraska Geology: Niobrara River Valley In Brown, Cherry, And Keya Paha Counties, R. M. Joeckel, L. M. Howard, S T. Tucker
Conservation and Survey Division: Faculty and Staff Publications
No abstract provided.
Nebraska Statewide Groundwater-Level Monitoring Report 2015, A. R. Young, M. E. Burbach, L. M. Howard
Nebraska Statewide Groundwater-Level Monitoring Report 2015, A. R. Young, M. E. Burbach, L. M. Howard
Conservation and Survey Division: Faculty and Staff Publications
No abstract provided.
Assessing The Relative Mobility Of Submarine Landslides From Deposit Morphology And Physical Properties: An Example From Kumano Basin, Nankai Trough, Offshore Japan, Zachary T. Moore
Theses and Dissertations--Earth and Environmental Sciences
A prominent landslide deposit in the Slope Basin seaward of the Megasplay Fault in the Nankai Trough was emplaced by a high-mobility landslide based on analysis of physical properties and seismic geomorphology. Slide acceleration is a critical variable that determines amplitude of slide-generated tsunami but is many times a variable with large uncertainty. In recent controlled laboratory experiments, the ratio of the shear stress to yield strength (defined as the Flow Factor) controls a wide spectrum of mass movement styles from slow, retrogressive failure to rapid, liquefied flows. Here, we apply this laboratory Flow Factor approach to a natural landslide …
Fluvial Responses To Growth Faulting In The West Pearl River, Louisiana, Stephen A. Prosser
Fluvial Responses To Growth Faulting In The West Pearl River, Louisiana, Stephen A. Prosser
Theses and Dissertations--Earth and Environmental Sciences
The Pearl River Delta (PRD) in southeastern Louisiana is an actively deforming deltaic complex displaying surface and near-surface evidence of growth faulting. Active growth faults in these environments are rarely identified at the surface, in part because the downthrown blocks often experience increased rates of sediment deposition leading to an obscured and low-relief, or entirely absent, surface expression. Faulting can be expressed in fluvial systems as changes in channel gradient, which often result in coincident changes in channel sinuosity, migration rates, planform deflections, and/or ponding features within the deformed zone. The study area is focused on a meander bend of …
Geologic Map Of The Welcome Quadrangle And An Adjacent Part Of The Wells Quadrangle, Elko County, Nevada, Allen J. Mcgrew, Arthur W. Snoke
Geologic Map Of The Welcome Quadrangle And An Adjacent Part Of The Wells Quadrangle, Elko County, Nevada, Allen J. Mcgrew, Arthur W. Snoke
Department of Earth, Environment and Sustainability Faculty Publications
Located in central Elko County, the Welcome and adjacent part of the Wells quadrangles expose a remarkable array of critical relationships for understanding the geologic history of the State of Nevada and the interior of the southwestern U.S. Cordillera. Covering the northern end of the East Humboldt Range and adjacent Clover Valley and Clover Hill, this map includes the northern terminus of the Ruby Mountains-East Humboldt Range metamorphic core complex. The oldest rocks in the State of Nevada (the gneiss complex of Angel Lake), and Nevada’s only exposures of Archean rock, form the core of a multikilometer scale, southward-closing recumbent …
Stream Bank Erosion Trends And Sediment Contributions In A Southwestern Missouri River, Ezekiel Allen Kuehn
Stream Bank Erosion Trends And Sediment Contributions In A Southwestern Missouri River, Ezekiel Allen Kuehn
Graduate Theses/Dissertations
Bank erosion can be a significant source of in-stream sediment that negatively affects water quality and aquatic habitat. However, assessments of the role that eroding banks play in suspended and bed sediment supply are rarely available to managers. The purpose of this study was to quantify bank erosion rates for a 7 km conservation easement the James River in southwest Missouri to evaluate the annual contributions of bank sediment to the channel. The objectives were to: (1) monitor an eroding 260 m bank to better understand short-term, reach scale bank erosion rates; (2) determine historical rates of bank erosion for …
A Potential Long-Lived Upper Cretaceous Paleodrainage System In The U.S. Southwestern Georgia-Southeastern Alabama Region, Daniel L. Black
A Potential Long-Lived Upper Cretaceous Paleodrainage System In The U.S. Southwestern Georgia-Southeastern Alabama Region, Daniel L. Black
Theses and Dissertations
The Gulf Coastal Plain unconformity separates crystalline basement of the Appalachian core from sedimentary units of the Coastal Plain. In the Columbus, Georgia region, basement rocks of the Uchee terrane are typically overlain by sands and gravels of the Tuscaloosa Formation. Sediments within the Tuscaloosa Formation indicate partial derivation from gneiss of the Columbus Metamorphic Complex, the nearby Pine Mountain belt and potentially rocks of Inner Piedmont-eastern Blue Ridge terranes. Mapping along the Coastal Plain unconformity near the Lower Chattahoochee River Valley indicates the presence of one or more large paleovalleys in the Upper Cretaceous sub-Coastal Plain surface that occupy …
Hydrophobic Organic Contaminant Transport Property Heterogeneity In The Borden Aquifer, Richelle M. Allen-King, Indra Kalinovich, David F. Dominic, Guohui Wang, Reid Polmanteer, Dana Divine
Hydrophobic Organic Contaminant Transport Property Heterogeneity In The Borden Aquifer, Richelle M. Allen-King, Indra Kalinovich, David F. Dominic, Guohui Wang, Reid Polmanteer, Dana Divine
Conservation and Survey Division: Faculty and Staff Publications
We determined that the spatial heterogeneity in aquifer properties governing the reactive transport of volatile organic contaminants is defined by the arrangement of lithofacies. We measured permeability (k) and perchloroethene sorption distribution coefficient (Kd) for lithofacies that we delineated for samples from the Canadian Forces Base Borden Aquifer. We compiled existing data and collected 57 new cores to characterize a 30 m section of the aquifer near the test location of Mackay et al. (1986). The k and Kd were measured for samples taken at six elevations from all cores to create a data set consisting of …
Hydrophobic Organic Contaminant Transport Property Heterogeneity In The Borden Aquifer, Richelle M. Allen-King, Indra Kalinovich, David F. Dominic, Guohui Wang, Reid Polmanteer, Dana Divine
Hydrophobic Organic Contaminant Transport Property Heterogeneity In The Borden Aquifer, Richelle M. Allen-King, Indra Kalinovich, David F. Dominic, Guohui Wang, Reid Polmanteer, Dana Divine
Conservation and Survey Division: Faculty and Staff Publications
We determined that the spatial heterogeneity in aquifer properties governing the reactive transport of volatile organic contaminants is defined by the arrangement of lithofacies. We measured permeability (k) and perchloroethene sorption distribution coefficient (Kd) for lithofacies that we delineated for samples from the Canadian Forces Base Borden Aquifer. We compiled existing data and collected 57 new cores to characterize a 30 m section of the aquifer near the test location of Mackay et al. (1986). The k and Kd were measured for samples taken at six elevations from all cores to create a data …
Field Observations And Modeling Of The 1957 Earthquake And Tsunami On The Islands Of The Four Mountains, Aleutian Islands, Alaska, Frances R. Griswold
Field Observations And Modeling Of The 1957 Earthquake And Tsunami On The Islands Of The Four Mountains, Aleutian Islands, Alaska, Frances R. Griswold
All Master's Theses
Due to a lack of research in the Aleutian Islands, a comprehensive history of the Aleutian subduction zone is not developed; however, this study indicates that the Aleutian subduction zone is capable of generating magnitude ~9 earthquakes or larger in addition to trans-Pacific tsunamis. Comparison of simulated runup and observed runup will help to determine the characteristics of rupture in the eastern Aleutians. A recent survey of the tsunami wrackline produced by the 1957 Great Aleutian earthquake (Mw 8.6) indicates runup up to 17.5 m in the Islands of the Four Mountains (presented here). Combined with other nearfield observations …
Quantifying Channel Responses To The Removal Of The Glines Canyon Dam In The Middle Reach Of The Elwha River, Washington, Bryon J. Free
Quantifying Channel Responses To The Removal Of The Glines Canyon Dam In The Middle Reach Of The Elwha River, Washington, Bryon J. Free
All Master's Theses
Four different study sites throughout the middle reach of the Elwha River were monitored before, during, and after the dam removal process over a period of two years from 2012-2014. The complexity of the river geometry was a major factor in the ability of the river to trap and accumulate the new influx of woody debris and sediment from the dam removal, which influenced the response of the river channel. The change that occurred was quantified by using repeat Terrestrial LiDAR (TLS), sediment distribution surveys, and large woody debris mapping techniques. The morphologic changes that occurred during this time were …
Holocene Sedimentology And Stratigraphy Of Coastal Sediments In An Arid Climate, Al Qahmah, Southern Red Sea, Saudi Arabia, Abdullah Ibrahim Nabhan
Holocene Sedimentology And Stratigraphy Of Coastal Sediments In An Arid Climate, Al Qahmah, Southern Red Sea, Saudi Arabia, Abdullah Ibrahim Nabhan
Doctoral Dissertations
"Holocene sedimentary deposits in Al Qahmah coast, southern Red Sea, in Saudi Arabia have been accumulated on an arid siliciclastic coast in a rift tectonic setting. This study provides a detail interpretation and analysis of sedimentary facies, stratigraphy, depositional environment, and major geological processes. Two studies have been undertaken. First, petrological study of composition and texture of modern sediments and facies mapping delineate facies distribution and mechanisms of sediment transport and deposition. A unique suite of complex riverine, wave, tidal, wind, and chemical and biological processes affect the composition, texture, and distribution of the facies. Second, the depositional environments of …
Understanding The Physiological Effects Of Suspended Material On Rainbow Trout (Oncorhynchus Mykiss), Tyler J. Weinhardt
Understanding The Physiological Effects Of Suspended Material On Rainbow Trout (Oncorhynchus Mykiss), Tyler J. Weinhardt
Theses and Dissertations (Comprehensive)
The effect of global warming on northern environments is becoming increasingly evident. Melting of underlying permafrost is associated with widespread impacts in these environments. The loss of permafrost results in a destabilizing of underlying sedimentary layers resulting in thermokarst slumping. When this occurs on a large scale (mega-slumping) soil material becomes mobilized and is carried into local streams and rivers. The purpose of this study is to examine the sub-lethal physiological effects that suspended material has on rainbow trout (Oncorhynchus mykiss) in the context of the Peel River Plateau. Juvenile rainbow trout were exposed (following Environment Canada exposure …
Habitat Assessment And Ecological Restoration Design For An Unnamed Tributary Of Stone Dam Creek, Conway, Arkansas, Paige E. Boyle, Mary C. Savin, James A. Mccarty, Marty D. Matlock
Habitat Assessment And Ecological Restoration Design For An Unnamed Tributary Of Stone Dam Creek, Conway, Arkansas, Paige E. Boyle, Mary C. Savin, James A. Mccarty, Marty D. Matlock
Discovery, The Student Journal of Dale Bumpers College of Agricultural, Food and Life Sciences
Urbanization can lead to increased sedimentation, erosion, pollution, and runoff into streams. The United States Environmental Protection Agency’s (USEPA) Rapid Bioassessment Protocols (RBPs) are sets of guidelines that can be used to assess a habitat’s sedimentology, hydrology, vegetation, and geomorphology to determine impairment. An unnamed tributary of Stone Dam Creek on the University of Central Arkansas (UCA) campus in Conway, Arkansas runs partially underground and through the urbanized UCA campus watershed. The stream was assessed using the USEPA’s RBPs to determine impairment of the stream, and received a RBP score of 71.2 out of 200 compared to 153.5 in a …
Applications Of Remote Sensing To The Study Of Estuarine Physics: Suspended Sediment Dynamics In The Columbia River Estuary, Austin Scott Hudson
Applications Of Remote Sensing To The Study Of Estuarine Physics: Suspended Sediment Dynamics In The Columbia River Estuary, Austin Scott Hudson
Dissertations and Theses
Estuarine circulation and its associated transport processes drive the environmental integrity of many near-shore habitats (the coastal ocean, rivers, estuaries and emergent wetlands). A thorough understanding and consideration of this circulation is, therefore, vital in the proper management of these habitats. The aim of this study is to bring together theory and new satellite observations in the Columbia River Estuary to increase our understanding of estuarine circulation and transport. Surface reflectance measurements gathered by the Moderate Imaging Spectroradiometer (MODIS) are first compared to in situ observations to develop an empirical model for remotely derived surface turbidity. Results indicate that MODIS …
Radiaxial-Fibrous And Fascicular-Optic Mg-Calcitic Cave Cements: A Characterization Using Electron Backscattered Diffraction (Ebsd), Detlev K. Richter, Adrian Immenhauser, Rolf Dieter Neuser, Augusto Mangini
Radiaxial-Fibrous And Fascicular-Optic Mg-Calcitic Cave Cements: A Characterization Using Electron Backscattered Diffraction (Ebsd), Detlev K. Richter, Adrian Immenhauser, Rolf Dieter Neuser, Augusto Mangini
International Journal of Speleology
Electron backscattered diffraction (EBSD) applied to crystal fabric research in speleothems aids in our understanding of the origin of those fabrics. A significant advantage of this approach is the three dimensional data set of crystal c-axes. Here, we show a rare case of both convergent (radiaxial-fibrous) and divergent (fascicular-optic) orientations of the c-axes in pool calcites. The seemingly defective structure of the calcite lattice resulting in radiaxial-fibrous crystal orientations is probably caused by differential incorporation of Mg during crystal growth. The observation that radiaxial-fibrous and fascicular-optic fabrics co-exist in the same pool environment is remarkable and documents the complexity of …
Qualitative Comparison Of Offset Surfaces Between The Central And Eastern Garlock Fault, Thomas M. Crane
Qualitative Comparison Of Offset Surfaces Between The Central And Eastern Garlock Fault, Thomas M. Crane
Electronic Theses, Projects, and Dissertations
The Garlock Fault consists of three distinct segments, known as western, central, and eastern, together reaching approximately 260 km from the San Andreas Fault to the southern end of Death Valley. Although published slip rates are available along the western and central Garlock Fault segments, little is currently known of the Garlock Fault earthquake history or slip rate farther east. Using LiDAR and satellite imagery, the central and eastern Garlock Fault segments were analyzed for visibly offset, fault-adjacent, geomorphic surfaces that may potentially be used for estimating slip rate. Qualitative methods of assessing preserved alluvial surface maturity were adapted and …
Thermal Impacts Of Salt On Sandstones And Mudstones In The Lusitanian Basin, Portugal, Brett Perry
Thermal Impacts Of Salt On Sandstones And Mudstones In The Lusitanian Basin, Portugal, Brett Perry
UNLV Theses, Dissertations, Professional Papers, and Capstones
In order to assess the impact of salt structures on paleotemperatures in adjacent sedimentary rocks, a field based study which quantified thermally driven diagenetic products as a function of distance from salt was undertaken. Several salt diapirs are now exposed at the surface of the Earth within the Lusitanian Basin and offered a unique opportunity to document paleothermal anomalies by studying thermally controlled diagenesis in adjacent, exposed Upper Jurassic rocks. Four transects were chosen within Upper Jurassic rocks that contained both sandstones and mudstones. Quartz cementation and albitization of feldspars, both of which are thermally driven processes, were quantified in …
Microstratigraphic Logging Of Calcite Fabrics In Speleothems As Tool For Palaeoclimate Studies, Silvia Frisia
Microstratigraphic Logging Of Calcite Fabrics In Speleothems As Tool For Palaeoclimate Studies, Silvia Frisia
International Journal of Speleology
The systematic documentation of calcite fabrics in stalagmites and flowstones provides robustness to palaeoclimate interpretation based on geochemical proxies, but it has been neglected because it is difficult to transform crystal morphologies into numerical values, and construct fabric time series. Here, general criteria that allow for coding fabrics of calcite composing stalagmites and flowstones is provided. Being based on known models of fabric development, the coding ascribes sequential numbers to each fabric, which reflect climate-related parameters, such as changes in drip rate variability, bio-mediation or diagenetic modifications. Acronyms are proposed for Columnar types, Dendritic, Micrite, Microsparite and Mosaic fabrics, whose …
Sedimentology Of The Upper Scotland Formation (Eocene), Barbados, Krishna Mahabir, Nazrul I. Khandaker, Jay P. Persaud, Stanley Schleifer
Sedimentology Of The Upper Scotland Formation (Eocene), Barbados, Krishna Mahabir, Nazrul I. Khandaker, Jay P. Persaud, Stanley Schleifer
Publications and Research
Representative samples collected from the Lower Scotland Formation (Eocene) outcropping in northeastern Barbados were investigated in conjunction with overall facies distribution and stratigraphic and sedimentological characteristics to interpret depositional environment and provenance of the fine-grained clastics. The Lower Scotland Formation is, for the most part, a fine-grained clastic-dominated sequence with occasional thin intercalations of gypsum, ironstone, and kaolinite. Distinctive deep-water-facies have been well-documented in dark gray shale units containing load cast, flutes, grooves and prods. In addition, turbiditic brown sandstone with a sharp erosive base and pelagic caps also characterize the base of the formation. Notable marine fauna observed include …
Field Trip Guidebook For The Nebraska Well Drillers Association, Duane A. Eversoll, Matt Joeckel, Lee Orton
Field Trip Guidebook For The Nebraska Well Drillers Association, Duane A. Eversoll, Matt Joeckel, Lee Orton
Conservation and Survey Division: Faculty and Staff Publications
No abstract provided.
Economic Geology Of The San Bernardino Mountains, California, Nicolette Deannah Grill
Economic Geology Of The San Bernardino Mountains, California, Nicolette Deannah Grill
Electronic Theses, Projects, and Dissertations
The San Bernardino Mountains are well known for their rich mining history, especially, gold in the mid-1800s and the current mining of one of the world’s largest deposits of high purity limestone. The purpose of this study was to compile new, current, and historical data of the major economic resources that are present and mining that has gone on in the San Bernardino Mountains. It is estimated that historical mining of the Holcomb Valley recovered $457,660,000 of gold or about 350,000 troy ounces based on samples collected for this study and 2013 gold price. The current major geologic resource is …
Geochemical Analysis Of Ice Age River Deposits From Turlock Lake Formation, Cemex Quarry Fresno, Ca, Ray J. Bargas
Geochemical Analysis Of Ice Age River Deposits From Turlock Lake Formation, Cemex Quarry Fresno, Ca, Ray J. Bargas
STAR Program Research Presentations
Nineteen bags of Pleistocene Age river deposited samples were taken from the Cemex Quarry in Fresno, CA. There are three formations in the area, deposited from rivers derived from glaciers, consisting of the Modesto, Riverbank, and Turlock Lake; youngest deposited to oldest respectively.
Phi sizes refer to each of the individual grains diameter, larger sized grains are in the negative spectrum while smaller grains are positive. Each sample has phi size bags that range in sizes from -5 to 4+, excluding phi size -2. For the phi sizes of -3 to -5, each individual rock was measured on its three …
Using Strat Columns To Interpret Sequence Stragraphy Of Glacial Driven Stream Deposits Of The Acient San Joaquin River, Kyle R. Scharton
Using Strat Columns To Interpret Sequence Stragraphy Of Glacial Driven Stream Deposits Of The Acient San Joaquin River, Kyle R. Scharton
STAR Program Research Presentations
The sedimentary deposits of the ancient San Joaquin River tell the story of river flow through three glacial periods. A strat column shows vertical changes in deposition throughout an outcrop. It can be used to extrapolate the energy level of the flow, and other features of the river at different depositional environments. By looking at trends through the column it is possible to determine how the river’s flow changed through time. Variances in the gravel size and whether it supports itself or is held together by the surrounding sand matrix give clues as to the rate of flow and how …
New Research In Cave Ledenica In Bukovi Vrh On Velebit Mt In Croatian Dinaric Karst, Mladen Garasic
New Research In Cave Ledenica In Bukovi Vrh On Velebit Mt In Croatian Dinaric Karst, Mladen Garasic
The International Workshop on Ice Caves
No abstract provided.
Effects Of Road Salt On Asylum Lake Geochemistry, Davina A. Wyman
Effects Of Road Salt On Asylum Lake Geochemistry, Davina A. Wyman
Masters Theses
Several studies indicate that seasonal applications of road deicers can lead to saline runoff entering surface water and groundwater, which can in turn change the chemistry, density, and physical mixing patterns of urban lakes. An investigation at Asylum Lake, an urban lake located near three major roadways, was conducted to determine the degree of road salt contamination in the lake, to determine if salt loading disrupts seasonal mixing patterns, and to determine the extent of redox stratification present due to eutrophic conditions. Samples were collected monthly from the deepest point in Asylum Lake over a 19-month period and analyzed for …
Macroinvertebrates And Excessive Fine Sediment Conditions In Oregon Coastal Streams, Patrick M. Edwards
Macroinvertebrates And Excessive Fine Sediment Conditions In Oregon Coastal Streams, Patrick M. Edwards
Dissertations and Theses
The Pacific Coastal ecoregion contains large tracts of economically important forest lands that also serve as critical stream habitat for endangered Salmonids. Excessive fine sediment deposition in streams of this region is a major environmental concern in the region but difficult to measure directly. The use of stream invertebrates to monitor fine sediment conditions in streams requires careful consideration of several important factors that complicate their use as bioindicators including high spatial and temporal variability and covariance with other environmental variables.
To evaluate the use of stream invertebrates as bioindicators of excessive fine sediment, three hypotheses were tested. The first …
Sedimentological And Stratigraphic Study Of A Falling-Stage Delta Complex In The Upper Cretaceous (Turonian) Ferron Sandstone Member Of The Mancos Shale, South-Central Utah, Usa, Fares Alaboud
Department of Earth and Atmospheric Sciences: Dissertations, Theses, and Student Research
The character and distribution of lithofacies in falling-stage deltas are incompletely documented. This paper presents a sedimentological and stratigraphic evaluation of a superbly-exposed interval of Cretaceous deltaic strata that are believed to be of falling stage origin. The studied interval forms part of the Upper Cretaceous (Turonian) Ferron Sandstone Member of the Mancos Shale in the southernmost Henry Mountains Basin of south-central Utah, USA. The interval of interest is exposed in three dimensions over a 20 km2 area in a series of canyon walls. Observed facies include fine-grained mudrocks (offshore basin), mudrocks with thinly interlaminated sandstone (prodelta), thinly interbedded …
Origin And Distribution Of The Mississippian–Pennsylvanian Boundary Unconformity In Marine Carbonate Successions With A Case Study Of The Karst Development Atop The Madison Formation In The Bighorn Basin, Wyoming, Lucien Nana Yobo
Department of Earth and Atmospheric Sciences: Dissertations, Theses, and Student Research
The causal mechanism of the widespread unconformity that encompasses the Mississippian – Pennsylvanian boundary remains poorly understood. This unconformity, first thought to be restricted to North America, is now known to be present in other regions of the globe. Possible causes for the unconformity include (1) sea level draw down from the onset of glaciation at start of the late Paleozoic ice age and (2) increased tectonic activity from the formation of the supercontinent of Pangea. Thus the origin of the unconformity is still poorly constrained.
This study examines possible causal mechanisms for the widespread unconformity that encompasses the Mississippian …
Stratigraphic Framework And Landsystem Correlation For Deposits Of The Saginaw Lobe, Michigan, Usa, Ivan R. Guzman
Stratigraphic Framework And Landsystem Correlation For Deposits Of The Saginaw Lobe, Michigan, Usa, Ivan R. Guzman
Masters Theses
Since the time of the Last Glacial Maximum (LGM) the south-central portion of the Lower Michigan Peninsula has been subject to several glacial advances and retreats by the Saginaw lobe. As part of the U.S Geological Survey Great Lakes Geological Mapping Coalition projects, several rotosonic borings were drilled between 2006 and 2013 in Barry, Kalamazoo and Calhoun Counties. Gamma ray logs and textural analyses were completed for each core. Five of these borings were selected according to their diamicton (till) content and correlated using water well logs and surficial geology maps. Glacial deposits such as diamicton serve as evidence of …